Background
In protocol 99-C-0143, we evaluated a new approach to allogeneic hematopoietic stem cell transplant (HSCT) that involved intensive host T cell ablation and graft augmentation with in vitro generated donor T helper 2 (Th2) cells. Rapid full donor engraftment occurred with this regimen; however, grade II to IV acute graft versus host disease (GVHD) was not significantly reduced in Th2 cell recipients. In an attempt to improve clinical results using Th2 cell graft engineering, this second-generation Th2 cell clinical trial was developed that incorporates the following interventions: (1) In an attempt to reduce transplant-related toxicity, this protocol now uses a very low-intensity host preparative chemotherapy; (2) In an attempt to reduce GVHD, this study will utilize Th2 cells expanded in the presence of the immune modulation agent, rapamycin (sirolimus), as murine Th2 cells grown in rapamycin reduce GVHD more effectively than control Th2 cells; (3) To further reduce GVHD, subjects will receive a short-course of sirolimus therapy in addition to standard cyclosporine GVHD prophylaxis; and (4) Using this novel low-intensity transplant platform, compare in a preliminary manner the post-transplant outcome of patients receiving pre-emptive donor lymphocyte infusion (DLI) using either Th2 cells or unmanipulated donor T cells.
Objectives
In the setting of human leukocyte antigen (HLA)-matched sibling allogeneic HSCT using GVHD prophylaxis of cyclosporine and short-course sirolimus, compare in a preliminary manner the safety, feasibility, alloengraftment, clinical anti-tumor effects, and GVHD rate of low-intensity Preparative Chemotherapy with pre-emptive DLI using either Th2 cells or unmanipulated T cells at day 14 post-HSCT.
Eligibility
Subjects that are 16 to 75 years of age that have a suitable 6/6 HLA-matched sibling donor are potentially eligible. Subjects with a diagnosis of acute or chronic leukemia, non-Hodgkin's lymphoma, Hodgkin's disease, multiple myeloma, or myelodysplastic syndrome are potentially eligible. Adequate kidney, cardiac, and pulmonary function are required.
Design
* Patients age 18 or older with lymphoma (all types) or chronic lymphocytic leukemia will be randomized just prior to the transplant regimen to receive DLI with either donor Th2 cells (cohort 1) or unmanipulated T cells (cohort 2); n=10 patients will be accrued to each arm provided that stopping rules pertaining to excessive GVHD or graft rejection are not met. For these randomized patients, the preparative regimen will consist of low-intensity fludarabine (120 mg/m(2)) plus cyclophosphamide (1200 mg/m(2)) and GVHD prophylaxis will consist of short-course, high-dose sirolimus followed by maintenance cyclosporine. Cohorts 1 and 2 will be compared in a preliminary manner with respect to their post-transplant outcome, in particular: (a) conversion of mixed chimerism to predominant donor chimerism; (b) rate and severity of classical acute and late acute GVHD at the day 100 and day 180 post-transplant time points; and (c) time to induction of leukemia/lymphoma remission (if entering transplant with disease) or time to relapse (if entering transplant in remission).
* Patients with non-lymphoma diagnoses, patients with lymphoma that are under the age of 18 and lymphoma patients that are projected to be unable to complete the protocol-defined therapy through day 180 post-transplant will not be randomized but will be treated on cohort 3 (n=40), which will evaluate transplantation without the Flu/Cy preparative regimen and with pre-emptive Th2 cell DLI. The primary objective of cohort 3 is to evaluate whether transplantation without a preparative regimen will reduce the rate of acute GVHD associated with Th2 cell DLI from 41% (the rate observed with the fludarabine/cyclophosphamide (Flu/Cy) preparative regimen) to a rate of 15% (6 cases out of 40).